(19) United States (12) Patent Application Publication (10 ... Woodbridge Foam Corporation, Mis sissauga, CA Appl. No.: 11/745,920 Filed: May 8, 2007 ... the foam within a relatively

(19) United States (12) Patent Application Publication (10) Pub. No.: US 2007/0208097 A1

Zhao et al. (43) Pub. Date:

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Sep. 6, 2007

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ISOCYANATE-BASED FOAMI HAVING IMPROVED ANT-YELLOWING PROPERTIES AND PROCESS FOR PRODUCTION THEREOF

Inventors: Wen Wei Zhao, Etobicoke (CA); Mladen Vidakovic, Toronto (CA); Eugene Smeianu, Thornhill (CA)

Correspondence Address: PATENT ADMINISTRATOR KATTEN MUCHIN ROSENMAN LLP 1025 THOMAS JEFFERSON STREET, N.W. EAST LOBBY SUTE 700 WASHINGTON, DC 20007-5201 (US)

Assignee: Woodbridge Foam Corporation, Mis sissauga, CA

Appl. No.: 11/745,920

Filed: May 8, 2007

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Related U.S. Application Data

Continuation of application No. 10/783,023, filed on Feb. 23, 2004.

Provisional application No. 60/448,476, filed on Feb. 21, 2003.

Publication Classification

Int. C. CSG 18/00 (2006.01) U.S. Cl. .............................................................. 521f172

ABSTRACT

There is described an isocyanate-based polymer foam hav ing improved anti-yellowing properties. The foam produced from a formulation comprising an isocyanate, a blowing agent, a first active hydrogen-containing compound and a second active hydrogen-containing compound different than the first active hydrogen-containing compound. The second active hydrogen-containing compound comprises an active hydrogen-containing phosphite compound. A process for producing Such a foam is also described.

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US 2007/0208097 A1

ISOCYANATE-BASED FOAMI HAVING IMPROVED ANT-YELLOWING PROPERTIES AND PROCESS

FOR PRODUCTION THEREOF

CROSS-REFERENCE TO RELATED APPLICATION

0001. The present application is a continuation of U.S. patent Application Ser. No. 10/783,023, filed Feb. 23, 2004, which claims the benefit under 35 U.S.C. S 119(e) of provi sional patent application Ser. No. 60/448,476, filed Feb. 21, 2003, the contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

0002) 1. Field of the Invention 0003. In one of its aspects, the present invention relates to an isocyanate-based polymer foam and to a process for production thereof. More particularly, the present invention relates to an isocyanate-based polymer foam, inter alia, having improved anti-yellowing properties compared to prior art foams. In another of its aspects, the present inven tion relates to a process for producing Such an isocyanate based polymer foam.

0004 2. Description of the Prior Art 0005 Isocyanate-based foams, such as polyurethane foams, are known in the art. Generally, those of skill in the art understand isocyanate-based polymers to be polyure thanes, polyureas, polyisocyanurates and mixtures thereof.

0006. It is also known in the art to produce foamed isocyanate-based polymers. Indeed, one of the advantages of isocyanate-based polymers compared to other polymer sys tems is that polymerization and foaming can occur in situ. This results in the ability to mould the polymer while it is forming and expanding.

0007 One of the conventional ways to produce a poly urethane foam is known as the “one-shot” technique. In this technique, the isocyanate, a suitable polyol, a catalyst, water (which acts as a reactive “blowing agent and can optionally be supplemented with one or more physical blowing agents) and other additives are mixed together at once using, for example, impingement mixing (e.g., high pressure). Gener ally, if one were to produce a polyurea, the polyol would be replaced with a suitable polyamine. A polyisocyanurate may result from cyclotrimerization of the isocyanate component. Urethane modified polyureas or polyisocyanurates are known in the art. In either scenario, the reactants would be intimately mixed very quickly using a Suitable mixing technique.

0008 Another technique for producing foamed isocyan ate-based polymers is known as the “prepolymer technique. In this technique, a prepolymer is produced by reacting polyol and isocyanate (in the case of a polyurethane) in an inert atmosphere to form a liquid polymer terminated with reactive groups (e.g., isocyanate moieties and active hydro gen moieties). To produce the foamed polymer, the prepoly mer is thoroughly mixed with a lower molecular weight polyol (in the case of producing a polyurethane) or a polyamine (in the case of producing a modified polyurea) in the presence of a curing agent and other additives, as needed.

Sep. 6, 2007

0009 Regardless of the technique used, one of the char acteristics of isocyanate-based foams, particularly polyure thane foams produced from formulations containing aro matic isocyanates (e.g., TDI, MDI and mixtures thereof), is their tendency to change colour after production. Specifi cally, polyurethane foams are known to change colour from slightly off-white directly after production to mustard yellow within hours or days after production. 0010. The colour change usually occurs on the surface of the foam within a relatively thin layer as a result of exposure to light (fluorescent or non-fluorescent) and atmosphere. This type of environmental induced colour change is differ ent from Scorching discoloration resulting from thermal induced degradation and does not have any significant impact on the physical properties of the foam. Nevertheless, the colour is unwelcome by most customers. 0011. It is known in the prior art that isocyanate-based foams produced from formulations containing aliphatic and/ or alicyclic-based isocyanates are less Susceptible to envi ronmentally induced discoloration when compared to iso cyanate-based foams produced from formulations containing aromatic-based isocyanates. See for example any one of the following: Japanese patent application S52 52997/1977, Japanese patent application H02-255817/1990, Japanese patent application H04-318016/1992 and U.S. Pat. No. 4,542,166 for teachings of yellowing-resistant isocyan ate-based foams produced from formulations containing aliphatic and/or alicyclic-based isocyanates. Unfortunately, isocyanate-based foams produced from formulations con taining aliphatic and/or alicyclic-based isocyanates have been met with very limited commercial Success as a result of relatively poor physical properties such as melting upon exposure to ultraviolet radiation, relatively low heat resis tance, relatively high material costs (i.e., of the isocyanates) and the like.

0012 To date the prior art has not developed a technique for slowing down or avoiding the post-production colour change in isocyanate-based foams such as polyurethane foams produced from formulations containing aromatic based isocyanates. 0013. Accordingly, there remains a need in the art an isocyanate-based polymer foam, particularly such foams produced from formulations containing aromatic-based iso cyanates having improved anti-yellowing properties. Ide ally, such a foam could be produced without the need to alter foam moulding equipment and other chemical components in the formulation used to produce the foam. Thus, it would be highly desirable to be able to produce such a foam by the addition to the formulation of a relatively low cost additive have no significant deleterious effect on the resultant foam

SUMMARY OF THE INVENTION

0014. It is an object of the present invention to obviate or mitigate at least one of the above-mentioned disadvantages of the prior art. 00.15 Accordingly, in one of its aspects, the present invention provides an isocyanate-based polymer foam pro duced from a formulation comprising an isocyanate, a blowing agent, a first active hydrogen-containing compound and a second active hydrogen-containing compound differ ent than the first active hydrogen-containing compound, the

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second active hydrogen-containing compound comprising an active hydrogen-containing phosphite compound. 0016 A molded isocyanate-based polymer foam pro duced from a formulation comprising an isocyanate, a blowing agent, a first active hydrogen-containing compound and a second active hydrogen-containing compound differ ent than the first active hydrogen-containing compound, the second active hydrogen-containing compound comprising an active hydrogen-containing phosphite compound. 0017. An isocyanate-based polymer foam produced from a formulation comprising an isocyanate, a blowing agent, a first active hydrogen-containing compound and a second active hydrogen-containing compound different than the first active hydrogen-containing compound, the second active hydrogen-containing compound comprising an active hydrogen-containing phosphite compound, with the proviso that the active hydrogen-containing phosphite compound is not present in any amount of 2 percent by weight of the foam.

0018. In another of its aspects, the present invention provides a process for producing a foamed isocyanate-based polymer comprising the steps of 0019 contacting an isocyanate, a blowing agent, a first active hydrogen-containing compound and a second active hydrogen-containing compound different than the first active hydrogen-containing compound to form a reaction mixture; and 0020 expanding the reaction mixture to produce the foamed isocyanate-based polymer 0021 wherein the second active hydrogen-containing compound comprises an active hydrogen-containing phos phite compound. 0022. Thus, the present inventors have surprisingly and unexpectedly discovered that incorporation of an active hydrogen-containing phosphite compound in an otherwise general formulation for production of an isocyanate-based polymeric foam results in a foam have significantly improved anti-yellowing properties. In addition, incorpora tion of Such an active hydrogen-containing phosphite com pound can, in many cases, confer flame retardant and/or load building properties to the foam. In preferred embodiments of the invention, incorporation of the active hydrogen-contain ing phosphite compound confers to the resultant foam improved anti-yellowing properties, improved flame retar dant properties and improved load building (or firmness) properties. In many cases, the allows for elimination of formulation compounds added specific to confer flame retar dant properties and displacement of a significant amount of load building ingredients such as copolymer polyols. With out wishing to be bound by any particular theory or mode of action it is believed that the active hydrogen-containing phosphite compound used to produce the presentisocyanate based foam reacts with the isocyanate component of the formulation. It is believed that this interaction is responsible, at least in part, for load building and flame retardant prop erties which conferred to the foam in addition to the improved anti-yellowing properties.

BRIEF DESCRIPTION OF THE DRAWINGS

0023 Embodiments of the present invention will be described with reference to the accompanying drawings, wherein like reference numerals denote like parts, and in which:

Sep. 6, 2007

0024 FIGS. 1 and 2 illustrate graphically the resistance to yellowing in respect of a number foams produced in the Examples below.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

0025 The present invention is related to a foamed iso cyanate-based polymer and to a process for production thereof. Preferably, the isocyanate-based polymer is selected from the group comprising polyurethane, polyurea, urea modified polyurethane, urethane-modified polyurea and iso cyanuarate-modified polyurethane. As is known in the art, the term “modified', when used in conjunction with a polyurethane or polyurea means that up to 50% of the polymer backbone forming linkages have been Substituted. 0026. The present foamed isocyanate-based polymer preferably is produced from a reaction mixture which com prises an isocyanate, a first active hydrogen-containing compound and a second active hydrogen-containing com pound which is different than the first active hydrogen containing compound.

0027. The selection of an isocyanate suitable for use in the reaction mixture is within the purview of a person skilled in the art. Generally, the isocyanate compound Suitable for use may be represented by the general formula:

Q(NCO),

wherein i is an integer of two or more and Q is an organic radical having the valence of i. Q may be a substituted or unsubstituted hydrocarbon group (e.g., an alkylene or arylene group). Moreover, Q may be represented by the general formula:

wherein Q' is an alkylene or arylene group and Z is chosen from the group comprising -O-, -O-Q'-, -CO , S-, -S-Q'-S- and -SO. . Examples of isocyanate

compounds which fall within the scope of this definition include hexamethylene diisocyanate, 1,8-diisocyanato-p- methane, xylyl diisocyanate, (OCNCHCHCHOCHO), 1-methyl-2,4-diisocyanatocyclohexane, phenylene diisocy anates, toluene diisocyanates, chlorophenylene diisocyan ates, diphenylmethane-4,4'-diisocyanate, naphthalene-1,5- diisocyanate, triphenylmethane-4,4',4'-triisocyanate and isopropylbenzene-alpha-4-diisocyanate.

0028. In another embodiment, Q may also represent a polyurethane radical having a valence of i. In this case Q(NCO) is a compound which is commonly referred to in the art as a prepolymer. Generally, a prepolymer may be prepared by reacting a stoichiometric excess of an isocyan ate compound (as defined hereinabove) with an active hydrogen-containing compound (as defined hereinafter), preferably the polyhydroxyl-containing materials or polyols described below. In this embodiment, the polyisocyanate may be, for example, used in proportions of from about 30 percent to about 200 percent stoichiometric excess with respect to the proportion of hydroxyl in the polyol. Since the process of the present invention may relate to the production of polyurea foams, it will be appreciated that in this embodi ment, the prepolymer could be used to prepare a polyure thane modified polyurea. 0029. In another embodiment, the isocyanate compound Suitable for use in the process of the present invention may

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be selected from dimers and trimers of isocyanates and diisocyanates, and from polymeric diisocyanates having the general formula:

IQ"(NCO), wherein bothi and are integers having a value of 2 or more, and Q" is a polyfunctional organic radical, and/or, as addi tional components in the reaction mixture, compounds hav ing the general formula:

L(NCO),

wherein i is an integer having a value of 1 or more and L is a monofunctional or polyfunctional atom or radical. Examples of isocyanate compounds which fall with the Scope of this definition include ethylphosphonic diisocyan ate, phenylphosphonic diisocyanate, compounds which con tain a =Si-NCO group, isocyanate compounds derived from sulphonamides (QSONCO), cyanic acid and thiocya nic acid.

0030 See also for example, British patent number 1,453, 258, for a discussion of suitable isocyanates. 0031. Non-limiting examples of suitable isocyanates include: 1.6-hexamethylene diisocyanate, 1,4-butylene diisocyanate, furfurylidene diisocyanate, 2,4-toluene diiso cyanate, 2,6-toluene diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'- diphenylpropane diisocyanate, 4,4'-diphenyl-3.3'-dimethyl methane diisocyanate, 1.5-naphthalene diisocyanate, 1-me thyl-2,4-diisocyanate-5-chlorobenzene, 2,4-diisocyanato-s- triazine, 1-methyl-2,4-diisocyanato cyclohexane, p-phe nylene diisocyanate, m-phenylene diisocyanate, 1,4- naphthalene diisocyanate, dianisidine diisocyanate, bitoluene diisocyanate, 1,4-xylylene diisocyanate, 1.3-Xy lylene diisocyanate, bis-(4-isocyanatophenyl)methane, bis (3-methyl-4-isocyanatophenyl)methane, polymethylene polyphenyl polyisocyanates and mixtures thereof. 0032 A particularly preferred class of isocyanates useful in the present isocyanate-based polymer foam is the so called aromatic-based isocyanates (e.g., those isocyanates based on diphenylmethane diisocyanate and/or toluene diisocyanate). 0033. A more preferred isocyanate is a mixture compris ing (i) a prepolymer of 4,4'-diphenylmethane diisocyanate and (ii) a carbodiamide-derivative based on 4,4'-diphenyl methane diisocyanate. Preferably the mixture comprises a weight ratio of (i):(ii) in the range of from about 1:1 to about 9:1.

0034. Another more preferred isocyanate is selected from the group comprising 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, modified 4,4'-diphenyl methane diisocyanate (modified to liquefy the diisocyanate at ambient temperature) and mixtures thereof. 0035. The most preferred isocyanate is selected from the group comprising 2,4-toluene diisocyanate, 2,6-toluene diisocyanate and mixtures thereof, for example, a mixture comprising from about 75 to about 85 percent by weight 2,4-toluene diisocyanate and from about 15 to about 25 percent by weight 2,6-toluene diisocyanate. 0.036 Preferably, the isocyanate used in the present pro cess has a functionality in the range of from about 2.0 to about 2.7, more preferably in the range of from about 2.0 to about 2.3.

Sep. 6, 2007

0037. The isocyanate preferably is used in an amount to provide an isocyanate index, inclusive of all reactive equiva lents in the reaction mixture, in the range of from about 60 to about 120, more preferably from about 70 to about 115, most preferably from about 85 to about 115. 0038 If the process is utilized to produce a polyurethane foam, the active hydrogen-containing compound is typically a polyol.

0.039 The choice of polyol suitable for use herein is within the purview of a person skilled in the art. For example, the polyol may be a hydroxyl-terminated backbone of a member selected from the group comprising polyether, polyester, polycarbonate, polydiene and polycaprolactone. Preferably, the polyol is selected from the group comprising hydroxyl-terminated polyhydrocarbons, hydroxyl-termi nated polyformals, fatty acid triglycerides, hydroxyl-termi nated polyesters, hydroxymethyl-terminated polyesters, hydroxymethyl-terminated perfluoromethylenes, polyalky leneether glycols, polyalkylenearyleneether glycols and polyalkyleneether triols. More preferred polyols are selected from the group comprising adipic acid-ethylene glycol poly ester, poly(butylene glycol), poly(propylene glycol) and hydroxyl-terminated polybutadiene—see, for example, Brit ish patent number 1,482,213, for a discussion of suitable polyols.

0040. A preferred polyol comprises polyether polyols. Preferably, such a polyether polyol has a molecular weight in the range of from about 200 to about 10,000, more preferably from about 2,000 to about 8,000, most preferably from about 4,000 to about 7,000.

0041 Further, it is possible to utilize a prepolymer tech nique to produce a polyurethane foam within the scope of the present invention. In one embodiment, it is contemplated that the prepolymer be prepared by reacting an excess of isocyanate with a polyol (as discussed above). The prepoly mer could then be reacted with further polyol (the same or different than the first polyol) to produce a polyurethane foam or an amine to produce a polyurea-modified polyure thane.

0042. If the process is utilized to produce a polyurea foam, the active hydrogen-containing compound comprises compounds wherein hydrogen is bonded to nitrogen. Pref erably Such compounds are selected from the group com prising polyamines, polyamides, polyimines and polyola mines, more preferably polyamines. Non-limiting examples of Such compounds include primary and secondary amine terminated polyethers. Preferably such polyethers have a molecular weight of greater than about 230 and a function ality of from 2 to 6. Such amine terminated polyethers are typically made from an appropriate initiator to which a lower alkylene oxide is added with the resulting hydroxyl terminated polyol being Subsequently aminated. If two or more alkylene oxides are used, they may be present either as random mixtures or as blocks of one or the other polyether. For ease of amination, it is especially preferred that the hydroxyl groups of the polyol be essentially all secondary hydroxyl groups. Typically, the amination step replaces the majority but not all of the hydroxyl groups of the polyol.

0043. In another embodiment, the first polyol may com prise a polymer polyol, also known as graft copolymer polyols. AS is known in the art, such polyols are generally

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polyether polyol dispersions which are filled with other organic polymers. Such polymer polyols are useful in load building or improving the hardness of the foam when compared to using unmodified polyols. Non-limiting examples of useful polymer polyols include: chain-growth copolymer polyols (e.g., containing particulate poly(acry lonitrile), poly(styrene-acrylonitrile) and mixtures thereof), and/or step-growth copolymer polyols (e.g., PolyHarnstoff Dispersions (PHD), polyisocyanate polyaddition (PIPA) polyols, epoxy dispersion polyols and mixtures thereof). For further information on polymer polyols, see, for example, Chapter 2 of FLEXIBLE FOAM FUNDAMENTALS, Her rington et al. (1991) and the references cited therein. If a polymer polyol is used, it is preferred to admix the polymer polyol with a base polyol. Generally, mixtures may be used which contain polymer polyol in an amount in the range of from about 5 to about 50 percent by weight of unmodified polyol present in the mixture. 0044) The second active hydrogen-containing compound comprises an active hydrogen-containing phosphite com pound.

0045. In one preferred embodiment, the second active hydrogen-containing compound is reactive with at least one other component of the formulation. 0046 Preferably, the active hydrogen-containing phos phite compound comprises one or more of the following moieties: hydroxyl, amino, carboxy, thiol and amido. More preferably, the active hydrogen-containing phosphite com pound comprises one more hydroxyl groups. 0047. In a more preferred embodiment, the active hydro gen-containing phosphite compound has the following for mula

wherein:

0048) R', R and R may be the same or different and each is selected from the group comprising a C-Cao ali phatic group optionally containing one or more heteroatoms, Cs-Cao aromatic group optionally containing one or more heteroatoms and a Cs-Cso araliphatic group optionally con taining one or more heteroatoms; 0049 X, X and X may be the same or different and each is selected from the group comprising hydroxyl, amino, carboxy, thiol and amido; and 0050 n is an integer in the range of from 1 to 10. 0051). In one preferred embodiment, R, R and Rare the same. In another preferred embodiment, R, R and R are different.

0052. In one preferred embodiment, X, X and X are the same. In another preferred embodiment, X, X and X are different.

0053) 0054) In a more preferred embodiment, R, R and Rare the same, X, X and X are the same and n is 1 or 3.

In one preferred embodiment, n is 1 or 3.

Sep. 6, 2007

0055 Specifically examples of compounds useful as the second active hydrogen-containing compound comprise tris (dipropyleneglycol)phosphite, heptakis(dipropyleneglycol )trisphosphite and mixtures thereof. Most preferably, the second active hydrogen-containing compound comprises tris(dipropyleneglycol)phosphite. 0056 Preferably, the second active hydrogen-containing compound is present in the formulation in an amount in the range from of about 0.1 to about 20, more preferably from about 0.5 to about 10, most preferably from about 0.5 to about 3.0, parts by weight per 100 parts by weight of the first active hydrogen-containing compound. 0057 The reaction mixture used to produce the present foamed isocyanate-based polymer typically will further comprise a blowing agent. As is known in the art water can be used as an indirect or reactive blowing agent in the production of foamed isocyanate-based polymers. Specifi cally, water reacts with the isocyanate forming carbon dioxide which acts as the effective blowing agent in the final foamed polymer product. Alternatively, the carbon dioxide may be produced by other means such as unstable com pounds which yield carbon dioxide (e.g., carbamates and the like). Optionally, direct organic blowing agents may be used in conjunction with water although the use of Such blowing agents is generally being curtailed for environmental con siderations. The preferred blowing agent for use in the production of the present foamed isocyanate-based polymer comprises water.

0058. It is known in the art that the amount of water used as an indirect blowing agent in the preparation of a foamed isocyanate-based polymer is conventionally in the range of from about 0.5 to as high as about 10 or more parts by weight, preferably from about 1.0 to about 3.0 parts by weight, based on 100 parts by weight of the total active hydrogen-containing compound content in the reaction mix ture. As is known in the art, the amount of water used in the production of a foamed isocyanate-based polymer typically is limited by the fixed properties expected in the foamed polymer and by the tolerance of the expanding foam towards self structure formation.

0059. The reaction mixture used to produce the present foamed isocyanate-based polymer typically will further comprise a catalyst. The catalyst used in the reaction mixture is a compound capable of catalyzing the polymerization reaction. Such catalysts are known, and the choice and concentration thereof in the reaction mixture is within the purview of a person skilled in the art. See, for example, U.S. Pat. Nos. 4,296,213 and 4,518,778 for a discussion of Suitable catalyst compounds. Non-limiting examples of Suit able catalysts include tertiary amines and/or organometallic compounds. It is also possible to utilize the so-called delayed action catalysts. Of course it will be understood by those skilled in the art that a combination of two or more catalysts may be suitably used.

0060. As will be clearly understood by those of skill in the art, it is contemplated that conventional additives in the polyurethane foam art can be used in the present process. Non-limiting examples of such additives include: filler materials, Surfactants, cell openers (e.g., silicone oils), cross linkers (e.g., low molecular weight reactive hydrogen-con taining compositions), pigments/dyes, flame retardants (e.g., halogenated organo-phosphoric acid compounds), inhibitors

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(e.g., weak acids), nucleating agents (e.g., diaZo com pounds), anti-oxidants, UV stabilizers (e.g., hydroxybenzo triazoles, Zinc dibutyl thiocarbamate, 2,6-ditertiary butylcat echol, hydroxybenzophenones, hindered amines and mixtures thereof), biocides, antistatic agents (e.g., ionizable metal salts, carboxylic acid salts, phosphate esters and mixtures thereof) and mixtures thereof The amounts of these additives conventionally used is within the purview of a person skilled in the art—see, for example, Chapter 2 of FLEXIBLE FOAM FUNDAMENTALS, Herrington et al. (1991) and the references cited therein. 0061 The manner by which the isocyanate, first active hydrogen-containing compound, second hydrogen-contain ing compound, blowing agent, catalyst and other additives (if present) are contacted in the present process is not particularly restricted. Thus, it is possible to preblend the components in a separate tank which is then connected to a Suitable mixing device for mixing with the blowing agent and catalyst. Alternatively, it is possible to preblend the active hydrogen-containing compound (e.g., polyol) with the blowing agent, catalyst, the second active hydrogen containing compound and other additives, if present, to form a resin. This resin preblend could then be fed to a suitable mixhead (high pressure or low pressure) which would also receive an independent stream of the isocyanate. The plas ticizer may be fed as a separate stream to the mixhead or into the resin stream via a suitable manifold or the like prior to the mixhead.

0062 Once the first and second active hydrogen-contain ing compounds, isocyanate, blowing agent, catalyst and other additives (if present) have been contacted and, ideally, mixed uniformly, a reaction mixture is formed. This reaction mixture is then expanded to produce the present isocyanate based polyurethane foam. As will be apparent to those of skill in the art, the process of the present invention is useful in the production of slabstock foam, molded articles and the like. The manner by which expansion of the reaction mixture is effected will be dictated by the type of foam being produced.

0063 Embodiments of the present invention will now be described with reference to the following Examples which should not be construed as limiting the scope of the inven tion. The term “pbw' used in the Examples refers to parts by weight.

0.064 used:

In the Examples, the following materials were

0065 E837, base polyol, commercially available from Lyondell:

0.066 E850, a 43% solids content copolymer (SAN) polyol, commercially available from Bayer; 0067 Phosphite #1, tris(dipropyleneglycol)phosphite; 0068 Lupranate T80, isocyanate (TDI), commercially available from BASF: 0069. MDI, isocyanate (MDI) commercially available from Dow:

0070 TM20, an 80/20 weight ratio blend of T80 and MDI;

0071 DC-5043, a surfactant, commercially available from Air Products;

Sep. 6, 2007

0072 PC77, a catalyst, commercially available from Air Products; 0073 Glycerine, a cross-linking agent, commercially available from Van Waters & Rogers: 0074 DEOA-LF, diethanolamine, a cross-linking agent commercially available from Air Products; 0075 Water, an indirect blowing agent; 0076) DabcoTM 33LV, a gelation catalyst, commercially available from Air Products;

0.077 FR-W, a flame retardant, commercially available from Akzo Chemicals;

0078 AB100, a flame retardant, commercially available from Albright & Wilson; and 0079 A-1, a blowing catalyst, commercially available from Witco.

EXAMPLES 1-3

0080) A number of molded foams were produced using formulations based on the amounts of E837, E850, Phos phite #1 and T80 set out in Table 1. The formulations also contained DC-5043, glycerine, DEOA-LF, water, 33-LV and A-1 in conventional amounts. As will be apparent, the formulations of Control A, Control B and Control C con tained no phosphite additive. Accordingly, foams produced from the formulations of Control A, Control B and Control C are outside the scope of the present invention and are provided for comparative purposes only. It should be noted that the formulations of Control A, Control B and Control C each contained FR-W in a conventional amount whereas FR-W, a conventional flame retardant additive, was not used in the Formulations of Examples 1-3. As is further apparent, the formulations of Examples 1-3 each comprised an active (or reactive) phosphite additive. Accordingly, foams pro duced from the formulations of Examples 1-3 are within the scope of the present invention. Further, in the formulations of Examples 1-3 the phosphite additive was present in an amount which displaced copolymer polyol in the formula tion of Control A in the a ratio of approximately 1:2 -e.g., in the formulation of Example 1, 2.7 parts by weight of phosphite additive displaces 5.4 parts by weight copolymer polyol in the formulation of Control A. 0081. The resultant foams were then subjected to physi cal testing. 0082 Specifically, the Indentation Force Deflection (IFD) at 50% compression of each foam was determined using ASTM D-3574-B1. The results are provided in Table 1. As can be seen, the foam produced in Example 1 had an IFD at 50% compression which is approximately the same as that of the foam produced in Control A notwithstanding the fact the formulation from which the foam of Example 1 was produced contained approximately 10% less copolymer polyol when compared to the formulation from which the foam of Control A was produced. Further, as can be seen, the foam produced in Example 2 had an IFD at 50% compres sion which is approximately the same as that of the foam produced in Control B notwithstanding the fact the formu lation from which the foam of Example 2 was produced contained approximately 15% less copolymer polyol when compared to the formulation from which the foam of Con

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trol B was produced. Still further, as can be seen, the foam produced in Example 3 had an IFD at 50% compression which is approximately the same as that of the foam pro duced in Control C notwithstanding the fact the formulation from which the foam of Example 3 was produced contained approximately 12% less copolymer polyol when compared to the formulation from which the foam of Control B was produced. 0083. The foams were also subject to flammability testing pursuant to FMVSS302. All foams were found to be self extinguishing. This was expected for the foams produced from the formulations of Control A, Control B and Control C since these contained a sufficient amount of a conventional flame retardant additive (i.e., FR-W). Surprisingly and unex pectedly, the foams produced from the formulations of Examples 1-3 were found to be self-extinguishing even though the starting formulations contained no conventional flame retardant additive.

0084. Accordingly, these Examples illustrate that the phosphite additive may be used to: (i) displace significant amounts (e.g., 12% and 15%) of copolymer polyol in the starting formulation without appreciable loss of firmness of the resultant foam, and (ii) eliminate the need to add a conventional flame retardant additive to the starting formu lation for the foam to pass flammability tests.

EXAMPLES 4-6

0085. A number of molded foams were produced using formulations based on the amounts of E837, E850, Phos phite #1 and T80 set out in Table 2. The formulations also contained DC-5043, glycerine, DEOA-LF, water, 33-LV. A-1 and AB100 in conventional amounts. As will be appar ent, the formulation of Control D contained no phosphite additive. Accordingly, foam produced from the formulation of Control D is outside the scope of the present invention and is provided for comparative purposes only. In contrast, the formulations of Examples 4-6 comprised various amounts of a phosphite additive. Accordingly, foams pro duced from the formulations of Examples 4-6 are within the Scope of the present invention. 0.086 The resultant foams were then subjected to testing to determine their anti-yellowing properties. The colour testing device used was an X-Rite Spectrophotometer (Model SP62) commercially available from X-Rite Inc. See the article entitled “Inhibition of the Discoloration of Poly urethane Foam Caused by Ultraviolet Light' by Valentine et al. (1992), 34" Annual Polyurethane Technical/Marketing Conference and the references cited therein for further information on the testing method. The results are reported in Table 3 as the Yellow Index b for each sample and are illustrated in FIG. 1.

0087 As shown, the foams produced from the formula tions of Examples 4-6 have increasingly improved anti yellowing (or whiteness) properties when compared to the foam produced from the formulation of Control D.

EXAMPLE 7

0088 A number of molded foams were produced using formulations based on the amounts of E837, E850, Phos phite #1 and T80 set out in Table 4. The formulations also contained DC-5043, glycerine, DEOA-LF, water, 33-LV and

Sep. 6, 2007

A-1 in conventional amounts. The formulations did not contain any conventional flame retardant additive. As will be apparent, the formulation of Control E contained no phos phite additive. Accordingly, foam produced from the formu lation of Control E is outside the scope of the present invention and is provided for comparative purposes only. In contrast, the formulation of Example 7 comprised 3 parts by weight of a phosphite additive. Accordingly, foam produced from the formulation of Examples 7 is within the scope of the present invention. 0089. The resultant foams where subject to the same physical testing as reported above for Examples 1-3. The results are provided in Table 4. As can be seen, the foam produced in Example 7 had an IFD at 50% compression which is approximately 10% greater than that of the foam produced in Control E notwithstanding the fact the formu lation from which the foam of Example 1 was produced contained approximately 6% less copolymer polyol when compared to the formulation from which the foam of Con trol E was produced. 0090 The foams were also subject to flammability testing pursuant to FMVSS302. The foam produced from the for mulation of Example 7 passed the test and was self-extin guishing whereas the foam produced from the formulation of Control E was not self-extinguishing. 0091. Further, the foam produced from the formulation of Example 7 had these improved properties with no appre ciable loss of valuable foam properties or characteristics.

EXAMPLES 8-13

0092. A number of molded foams were produced using formulations based on the amounts of E837, E850, Phos phite #1, T80, TM20 and MDI set out in Table 2. The formulations also contained DC-5043, glycerine, DEOA-LF, water, 33-LV, A-1 and AB100 (or equivalents) in conven tional amounts. As will be apparent, the formulations of Control F. Control G, and Control H contained no phosphite additive. Accordingly, foams produced from the formulation of Control F. Control G and Control Hare outside the scope of the present invention and are provided for comparative purposes only. In contrast, the formulations of Examples 8-13 comprised various amounts of a phosphite additive. Accordingly, foams produced from the formulations of Examples 8-13 are within the scope of the present invention. 0093. The resultant foams were then subjected to testing to determine their anti-yellowing properties as described above for the foams of Examples 4-6. The period of aging was 72 hours after production with storage under constant fluorescent lights and ambient temperature and humidity.

0094. As shown, the foams produced from the formula tions of Examples 8 and 9 have increasingly improved anti-yellowing (or whiteness) properties when compared to the foam produced from the formulation of Control F. Further, the foams produced from the formulations of Examples 10 and 11 have increasingly improved anti-yel lowing (or whiteness) properties when compared to the foam produced from the formulation of Control G. Still further, the foams produced from the formulations of Examples 12 and 13 have increasingly improved anti-yellowing (or white ness) properties when compared to the foam produced from the formulation of Control H.

US 2007/0208097 A1

TABLE 1.

Example

Ingredient Control A 1 Control B 2 Control C 3

E850 36.6 31.2 35.7 30.2 46.7 41.0

E837 63.4 66.1 64.3 67.0 53.3 56.3

Phosphitefil O.O 2.7 O.O 2.7 O.O 2.7

T80 (index) 97 97 96 96 96 96

50% IFD (N) 3O4 306 211 218 253 255

O095

TABLE 2

Example

Ingredient Control D 4 5 6

E850 SO.OO 49.OO 48.OO 47.00

E837 SO.OO SO.OO SO.OO SO.OO

Phosphitefil O.OO 1.OO 2.OO 3.00

T80 (index) 1OO 100 100 1OO

0096)

TABLE 3

Yellow Index b

Example

Foam age (hir) Control D 4 5 6

O.S O.8 O.2 O.O O.O 16 19.2 12.5 9.8 8.1 24 22.3 14.6 12.1 9.7 40 25.8 18.5 15.2 12.6 48 26.6 19.9 16.3 13.4 72 29.0 23.7 2O.O 16.5 144 34.0 30.7 27.1 24.O 216 37.2 35.5 32.6 29.5

0097

TABLE 4

Example

Ingredient Control E 7

E850 SO.OO 47.00 E837 SO.OO SO.OO Phosphitefil O.OO 3.00

T80 (index) 100 1OO 50% IFD (N) 287.5 3O3.6

Sep. 6, 2007

0098)

TABLE 5

Example

Ingredient Control F 8 9

E850 SO.OO SO.OO SO.OO E837 SO.OO SO.OO SO.OO Phosphitefil O.OO O.SO 3.00 Isocyanate Index TDI47.30 TDI47.30 TDI47.30 b Value 36.12 34.OS 21.99

0099)

TABLE 6

Example

Ingredient Control G 10 11

E850 SO.OO SO.OO SO.OO E837 SO.OO SO.OO SO.OO Phosphitefil O.OO O.SO 3.00 Isocyanate Index TM2O,47.30 TM2O,47.30 TM2O,47.30 b Value 39.57 35.21 23.94

0100

TABLE 7

Example

Ingredient Control H 12 13

E850 3.00 3.00 3.00 E837 73.20 73.20 73.20 Phosphitefil O.O O.S 3.0 Isocyanate. Amount MDIF87.45 MDIF87.45 MDIF87.45 b Value 17.09 13.95 9.81

0101) While this invention has been described with ref erence to illustrative embodiments and examples, the description is not intended to be construed in a limiting sense. Thus, various modifications of the illustrative embodiments, as well as other embodiments of the inven tion, will be apparent to persons skilled in the art upon reference to this description. For example, it is possible to use the active hydrogen-containing phosphite compound as is in the formulation or to incorporate its functionality into the other active hydrogen-containing compound (i.e., the polyol or polyoxyalkylene if a polyurethane foam is being produced). Thus, as an example, the active hydrogen-con taining phosphite compound could be used as a starter or initiator compound in the production of the polyol thereby avoiding the need to use a conventional polyol and the active hydrogen-containing phosphite compound as separate ingre dients in the formulation used to produce the foam. The resulting phosphite-derivatized active hydrogen-contain ing compound (e.g., polyol) could be used as is in the formulation or in the form of an NCO-terminated prepoly mer or an active hydrogen-terminated prepolymer (prepoly mers are generally discussed above). It is therefore contem plated that the appended claims will cover any Such modifications or embodiments.

0102 All publications, patents and patent applications referred to herein are incorporated by reference in their

US 2007/0208097 A1

entirety to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated by reference in its entirety. What is claimed is:

1. An isocyanate-based polymer foam produced from a formulation comprising an isocyanate, a blowing agent, a first active hydrogen-containing compound and a second active hydrogen-containing compound different than the first active hydrogen-containing compound, the second active hydrogen-containing compound consisting essen tially of an anti-yellowing amount of an active hydrogen containing phosphite compound.

2. The foam defined in claim 1, wherein the second active hydrogen-containing compound is reactive with at least one other component of the formulation.

3. The foam defined in claim 1, wherein active hydrogen containing phosphite compound comprises one or more of the following moieties: hydroxyl, amino, carboxy, thiol and amido.

4. The foam defined in claim 1, wherein the active hydrogen-containing phosphite compound comprises one more hydroxyl groups.

5. The foam defined in claim 1, wherein the active hydrogen-containing phosphite compound has the following formula

O-R-X

wherein:

R", R and R may be the same or different and each is selected from the group comprising a C-C aliphatic group optionally containing one or more heteroatoms, Cs-Cao aromatic group optionally containing one or more heteroatoms and a Cs-Cso araliphatic group optionally containing one or more heteroatoms;

X, X and X may be the same or different and each is Selected from the group comprising hydroxyl, amino, carboxy, thiol and amido; and

n is an integer in the range of from 1 to 10. 6. The foam defined in claim 1, wherein R, R and Rare

the same. 7. The foam defined in claim 1, wherein R, R and Rare

different. 8. The foam defined in claim 1, wherein X', X and X are

the same. 9. The foam defined in claim 1, wherein X, X and X are

different. 10. The foam defined in claim 1, wherein: R', RandR

are the same, and X, X and X are the same. 11. The foam defined in claim 1, wherein the second

active hydrogen-containing compound comprises tris(dipro pyleneglycol)phosphite.

12. The foam defined in claim 1, wherein the second active hydrogen-containing compound is present in the formulation in an amount in the range from of about 0.5 to about 3.0 parts by weight per 100 parts by weight of the first active hydrogen-containing compound.

13. The foam defined in claim 1, wherein the first active hydrogen-containing compound comprises a polyol.

Sep. 6, 2007

14. The foam defined in claim 1, wherein the isocyanate is selected from the group comprising 2,4-toluene diisocy anate, 2,6-toluene diisocyanate and mixtures thereof.

15. The foam defined in claim 1, wherein the isocyanate is selected from the group consisting essentially of (i) 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate and mixtures thereof, and (ii) mixtures of (i) with an isocyanate selected from the group comprising 2,4-toluene diisocyanate, 2,6-toluene diisocyanate and mix tures thereof.

16. The foam defined in claim 1, wherein the blowing agent comprises water.

17. The foam defined in claim 16, wherein the water is used in an amount in the range of from about 1.0 to about 10 parts by weight per 100 parts by weight of active hydrogen-containing compound used in the reaction mix ture.

18. A process for producing a foamed isocyanate-based polymer comprising the steps of

contacting an isocyanate, a blowing agent, a first active hydrogen-containing compound and a second active hydrogen-containing compound different than the first active hydrogen-containing compound and a blowing agent to form a reaction mixture; and

expanding the reaction mixture to produce the foamed isocyanate-based polymer;

wherein the second active hydrogen-containing com pound consists essentially of an anti-yellowing amount of an active hydrogen-containing phosphite compound.

19. The process defined in claim 18, wherein the second active hydrogen-containing compound is reactive with at least one other component of the formulation.

20. The process defined in claim 18, wherein active hydrogen-containing phosphite compound comprises one or more of the following moieties: hydroxyl, amino, carboxy, thiol and amido.

21. The process defined in claim 18, wherein the active hydrogen-containing phosphite compound comprises one more hydroxyl groups.

22. The process defined in claim 18, wherein the active hydrogen-containing phosphite compound has the following formula

wherein:

R", R and R may be the same or different and each is Selected from the group comprising a C-Cao aliphatic group optionally containing one or more heteroatoms, Cs-Cao aromatic group optionally containing one or more heteroatoms and a Cs-Cso araliphatic group optionally containing one or more heteroatoms;

X, X and X may be the same or different and each is Selected from the group comprising hydroxyl, amino, carboxy, thiol and amido; and

n is an integer in the range of from 1 to 10.

US 2007/0208097 A1

23. The process defined in claim 18, wherein R', R and Rare the same.

24. The process defined in claim 18, wherein R', R and Rare different.

25. The process defined in claim 18, wherein X', X and X are the same.

26. The process defined in claim 18, wherein X', X and X are different.

27. The process defined in claim 18, wherein: R', R and Rare the same, and X, X and X are the same.

28. The process defined in claim 18, wherein the second active hydrogen-containing compound comprises tris(dipro pyleneglycol)phosphite.

29. The process defined in claim 18, wherein the second active hydrogen-containing compound is present in the reaction in an amount in the range from of about 0.5 to about 3.0 parts by weight per 100 parts by weight of the first active hydrogen-containing compound.

30. The process defined in claim 18, wherein the first active hydrogen-containing compound comprises a polyol.

31. The process defined in claim 18, wherein the isocy anate is selected from the group comprising 2,4-toluene diisocyanate, 2,6-toluene diisocyanate and mixtures thereof.

32. The process defined in claim 18, wherein the isocy anate is selected from the group consisting essentially of (i) 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate and mixtures thereof, and (ii) mixtures of (i) with an isocyanate selected from the group comprising 2,4-toluene diisocyanate, 2,6-toluene diisocyanate and mix tures thereof.

33. The process defined in claim 18, wherein the blowing agent comprises water.

34. The process defined in claim 33, wherein the water is used in an amount in the range of from about 1.0 to about 10 parts by weight per 100 parts by weight of active hydrogen-containing compound used in the reaction mix ture.

35. A molded isocyanate-based polymer foam produced from a formulation comprising an isocyanate, a blowing agent, a first active hydrogen-containing compound and a second active hydrogen-containing compound different than the first active hydrogen-containing compound, the second active hydrogen-containing compound consisting essen tially of an anti-yellowing amount of an active hydrogen containing phosphite compound.

36. An isocyanate-based polymer foam produced from a formulation comprising an isocyanate, a blowing agent, a first active hydrogen-containing compound and a second

Sep. 6, 2007

active hydrogen-containing compound different than the first active hydrogen-containing compound, the second active hydrogen-containing compound consisting essen tially of an anti-yellowing amount of an active hydrogen containing phosphite compound, with the proviso that the active hydrogen-containing phosphite compound is not present in an amount of 2 percent by weight of the foam.

37. An isocyanate-based polymer foam produced from a formulation comprising isocyanate, a blowing agent, a first active hydrogen-containing compound and a second active hydrogen-containing compound different than the first active hydrogen-containing compound, the second active hydrogen-containing compound consisting essentially of an anti-yellowing amount of an active hydrogen-containing phosphite compound, wherein, for a period of 48 hours after production, the foam has a B* value of up to about 90 percent of the B* value of a control foam produced from a control formulation identical to the formulation with the proviso that the control formulation is free of the second active hydrogen-containing compound.



k k k k k

(19) United States (12) Patent Application Publication (10 ... Woodbridge Foam Corporation, Mis sissauga, CA Appl. No.: 11/745,920 Filed: May 8, 2007 ... the foam within a relatively

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